// Copyright 2011 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// WebP encoder: main entry point
//
// Author: Skal (pascal.massimino@gmail.com)
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "./cost.h"
#include "./vp8enci.h"
#include "./vp8li.h"
#include "../utils/utils.h"
// #define PRINT_MEMORY_INFO
#ifdef PRINT_MEMORY_INFO
#include <stdio.h>
#endif
//------------------------------------------------------------------------------
int WebPGetEncoderVersion(void) {
return (ENC_MAJ_VERSION << 16) | (ENC_MIN_VERSION << 8) | ENC_REV_VERSION;
}
//------------------------------------------------------------------------------
// VP8Encoder
//------------------------------------------------------------------------------
static void ResetSegmentHeader(VP8Encoder* const enc) {
VP8EncSegmentHeader* const hdr = &enc->segment_hdr_;
hdr->num_segments_ = enc->config_->segments;
hdr->update_map_ = (hdr->num_segments_ > 1);
hdr->size_ = 0;
}
static void ResetFilterHeader(VP8Encoder* const enc) {
VP8EncFilterHeader* const hdr = &enc->filter_hdr_;
hdr->simple_ = 1;
hdr->level_ = 0;
hdr->sharpness_ = 0;
hdr->i4x4_lf_delta_ = 0;
}
static void ResetBoundaryPredictions(VP8Encoder* const enc) {
// init boundary values once for all
// Note: actually, initializing the preds_[] is only needed for intra4.
int i;
uint8_t* const top = enc->preds_ - enc->preds_w_;
uint8_t* const left = enc->preds_ - 1;
for (i = -1; i < 4 * enc->mb_w_; ++i) {
top[i] = B_DC_PRED;
}
for (i = 0; i < 4 * enc->mb_h_; ++i) {
left[i * enc->preds_w_] = B_DC_PRED;
}
enc->nz_[-1] = 0; // constant
}
// Mapping from config->method_ to coding tools used.
//-------------------+---+---+---+---+---+---+---+
// Method | 0 | 1 | 2 | 3 |(4)| 5 | 6 |
//-------------------+---+---+---+---+---+---+---+
// fast probe | x | | | x | | | |
//-------------------+---+---+---+---+---+---+---+
// dynamic proba | ~ | x | x | x | x | x | x |
//-------------------+---+---+---+---+---+---+---+
// fast mode analysis| | | | | x | x | x |
//-------------------+---+---+---+---+---+---+---+
// basic rd-opt | | | | x | x | x | x |
//-------------------+---+---+---+---+---+---+---+
// disto-refine i4/16| x | x | x | | | | |
//-------------------+---+---+---+---+---+---+---+
// disto-refine uv | | x | x | | | | |
//-------------------+---+---+---+---+---+---+---+
// rd-opt i4/16 | | | ~ | x | x | x | x |
//-------------------+---+---+---+---+---+---+---+
// token buffer (opt)| | | | x | x | x | x |
//-------------------+---+---+---+---+---+---+---+
// Trellis | | | | | | x |Ful|
//-------------------+---+---+---+---+---+---+---+
// full-SNS | | | | | x | x | x |
//-------------------+---+---+---+---+---+---+---+
static void MapConfigToTools(VP8Encoder* const enc) {
const WebPConfig* const config = enc->config_;
const int method = config->method;
const int limit = 100 - config->partition_limit;
enc->method_ = method;
enc->rd_opt_level_ = (method >= 6) ? RD_OPT_TRELLIS_ALL
: (method >= 5) ? RD_OPT_TRELLIS
: (method >= 3) ? RD_OPT_BASIC
: RD_OPT_NONE;
enc->max_i4_header_bits_ =
256 * 16 * 16 * // upper bound: up to 16bit per 4x4 block
(limit * limit) / (100 * 100); // ... modulated with a quadratic curve.
enc->thread_level_ = config->thread_level;
enc->do_search_ = (config->target_size > 0 || config->target_PSNR > 0);
if (!config->low_memory) {
#if !defined(DISABLE_TOKEN_BUFFER)
enc->use_tokens_ = (enc->rd_opt_level_ >= RD_OPT_BASIC); // need rd stats
#endif
if (enc->use_tokens_) {
enc->num_parts_ = 1; // doesn't work with multi-partition
}
}
}
// Memory scaling with dimensions:
// memory (bytes) ~= 2.25 * w + 0.0625 * w * h
//
// Typical memory footprint (614x440 picture)
// encoder: 22111
// info: 4368
// preds: 17741
// top samples: 1263
// non-zero: 175
// lf-stats: 0
// total: 45658
// Transient object sizes:
// VP8EncIterator: 3360
// VP8ModeScore: 872
// VP8SegmentInfo: 732
// VP8EncProba: 18352
// LFStats: 2048
// Picture size (yuv): 419328
static VP8Encoder* InitVP8Encoder(const WebPConfig* const config,
WebPPicture* const picture) {
VP8Encoder* enc;
const int use_filter =
(config->filter_strength > 0) || (config->autofilter > 0);
const int mb_w = (picture->width + 15) >> 4;
const int mb_h = (picture->height + 15) >> 4;
const int preds_w = 4 * mb_w + 1;
const int preds_h = 4 * mb_h + 1;
const size_t preds_size = preds_w * preds_h * sizeof(*enc->preds_);
const int top_stride = mb_w * 16;
const size_t nz_size = (mb_w + 1) * sizeof(*enc->nz_) + WEBP_ALIGN_CST;
const size_t info_size = mb_w * mb_h * sizeof(*enc->mb_info_);
const size_t samples_size =
2 * top_stride * sizeof(*enc->y_top_) // top-luma/u/v
+ WEBP_ALIGN_CST; // align all
const size_t lf_stats_size =
config->autofilter ? sizeof(*enc->lf_stats_) + WEBP_ALIGN_CST : 0;
uint8_t* mem;
const uint64_t size = (uint64_t)sizeof(*enc) // main struct
+ WEBP_ALIGN_CST // cache alignment
+ info_size // modes info
+ preds_size // prediction modes
+ samples_size // top/left samples
+ nz_size // coeff context bits
+ lf_stats_size; // autofilter stats
#ifdef PRINT_MEMORY_INFO
printf("===================================\n");
printf("Memory used:\n"
" encoder: %ld\n"
" info: %ld\n"
" preds: %ld\n"
" top samples: %ld\n"
" non-zero: %ld\n"
" lf-stats: %ld\n"
" total: %ld\n",
sizeof(*enc) + WEBP_ALIGN_CST, info_size,
preds_size, samples_size, nz_size, lf_stats_size, size);
printf("Transient object sizes:\n"
" VP8EncIterator: %ld\n"
" VP8ModeScore: %ld\n"
" VP8SegmentInfo: %ld\n"
" VP8EncProba: %ld\n"
" LFStats: %ld\n",
sizeof(VP8EncIterator), sizeof(VP8ModeScore),
sizeof(VP8SegmentInfo), sizeof(VP8EncProba),
sizeof(LFStats));
printf("Picture size (yuv): %ld\n",
mb_w * mb_h * 384 * sizeof(uint8_t));
printf("===================================\n");
#endif
mem = (uint8_t*)WebPSafeMalloc(size, sizeof(*mem));
if (mem == NULL) {
WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
return NULL;
}
enc = (VP8Encoder*)mem;
mem = (uint8_t*)WEBP_ALIGN(mem + sizeof(*enc));
memset(enc, 0, sizeof(*enc));
enc->num_parts_ = 1 << config->partitions;
enc->mb_w_ = mb_w;
enc->mb_h_ = mb_h;
enc->preds_w_ = preds_w;
enc->mb_info_ = (VP8MBInfo*)mem;
mem += info_size;
enc->preds_ = ((uint8_t*)mem) + 1 + enc->preds_w_;
mem += preds_size;
enc->nz_ = 1 + (uint32_t*)WEBP_ALIGN(mem);
mem += nz_size;
enc->lf_stats_ = lf_stats_size ? (LFStats*)WEBP_ALIGN(mem) : NULL;
mem += lf_stats_size;
// top samples (all 16-aligned)
mem = (uint8_t*)WEBP_ALIGN(mem);
enc->y_top_ = (uint8_t*)mem;
enc->uv_top_ = enc->y_top_ + top_stride;
mem += 2 * top_stride;
assert(mem <= (uint8_t*)enc + size);
enc->config_ = config;
enc->profile_ = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;
enc->pic_ = picture;
enc->percent_ = 0;
MapConfigToTools(enc);
VP8EncDspInit();
VP8DefaultProbas(enc);
ResetSegmentHeader(enc);
ResetFilterHeader(enc);
ResetBoundaryPredictions(enc);
VP8EncDspCostInit();
VP8EncInitAlpha(enc);
// lower quality means smaller output -> we modulate a little the page
// size based on quality. This is just a crude 1rst-order prediction.
{
const float scale = 1.f + config->quality * 5.f / 100.f; // in [1,6]
VP8TBufferInit(&enc->tokens_, (int)(mb_w * mb_h * 4 * scale));
}
return enc;
}
static int DeleteVP8Encoder(VP8Encoder* enc) {
int ok = 1;
if (enc != NULL) {
ok = VP8EncDeleteAlpha(enc);
VP8TBufferClear(&enc->tokens_);
WebPSafeFree(enc);
}
return ok;
}
//------------------------------------------------------------------------------
static double GetPSNR(uint64_t err, uint64_t size) {
return (err > 0 && size > 0) ? 10. * log10(255. * 255. * size / err) : 99.;
}
static void FinalizePSNR(const VP8Encoder* const enc) {
WebPAuxStats* stats = enc->pic_->stats;
const uint64_t size = enc->sse_count_;
const uint64_t* const sse = enc->sse_;
stats->PSNR[0] = (float)GetPSNR(sse[0], size);
stats->PSNR[1] = (float)GetPSNR(sse[1], size / 4);
stats->PSNR[2] = (float)GetPSNR(sse[2], size / 4);
stats->PSNR[3] = (float)GetPSNR(sse[0] + sse[1] + sse[2], size * 3 / 2);
stats->PSNR[4] = (float)GetPSNR(sse[3], size);
}
static void StoreStats(VP8Encoder* const enc) {
WebPAuxStats* const stats = enc->pic_->stats;
if (stats != NULL) {
int i, s;
for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
stats->segment_level[i] = enc->dqm_[i].fstrength_;
stats->segment_quant[i] = enc->dqm_[i].quant_;
for (s = 0; s <= 2; ++s) {
stats->residual_bytes[s][i] = enc->residual_bytes_[s][i];
}
}
FinalizePSNR(enc);
stats->coded_size = enc->coded_size_;
for (i = 0; i < 3; ++i) {
stats->block_count[i] = enc->block_count_[i];
}
}
WebPReportProgress(enc->pic_, 100, &enc->percent_); // done!
}
int WebPEncodingSetError(const WebPPicture* const pic,
WebPEncodingError error) {
assert((int)error < VP8_ENC_ERROR_LAST);
assert((int)error >= VP8_ENC_OK);
((WebPPicture*)pic)->error_code = error;
return 0;
}
int WebPReportProgress(const WebPPicture* const pic,
int percent, int* const percent_store) {
if (percent_store != NULL && percent != *percent_store) {
*percent_store = percent;
if (pic->progress_hook && !pic->progress_hook(percent, pic)) {
// user abort requested
WebPEncodingSetError(pic, VP8_ENC_ERROR_USER_ABORT);
return 0;
}
}
return 1; // ok
}
//------------------------------------------------------------------------------
int WebPEncode(const WebPConfig* config, WebPPicture* pic) {
int ok = 0;
if (pic == NULL)
return 0;
WebPEncodingSetError(pic, VP8_ENC_OK); // all ok so far
if (config == NULL) // bad params
return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
if (!WebPValidateConfig(config))
return WebPEncodingSetError(pic, VP8_ENC_ERROR_INVALID_CONFIGURATION);
if (pic->width <= 0 || pic->height <= 0)
return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
if (pic->width > WEBP_MAX_DIMENSION || pic->height > WEBP_MAX_DIMENSION)
return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
if (pic->stats != NULL) memset(pic->stats, 0, sizeof(*pic->stats));
if (!config->lossless) {
VP8Encoder* enc = NULL;
if (!config->exact) {
WebPCleanupTransparentArea(pic);
}
if (pic->use_argb || pic->y == NULL || pic->u == NULL || pic->v == NULL) {
// Make sure we have YUVA samples.
if (config->preprocessing & 4) {
if (!WebPPictureSmartARGBToYUVA(pic)) {
return 0;
}
} else {
float dithering = 0.f;
if (config->preprocessing & 2) {
const float x = config->quality / 100.f;
const float x2 = x * x;
// slowly decreasing from max dithering at low quality (q->0)
// to 0.5 dithering amplitude at high quality (q->100)
dithering = 1.0f + (0.5f - 1.0f) * x2 * x2;
}
if (!WebPPictureARGBToYUVADithered(pic, WEBP_YUV420, dithering)) {
return 0;
}
}
}
enc = InitVP8Encoder(config, pic);
if (enc == NULL) return 0; // pic->error is already set.
// Note: each of the tasks below account for 20% in the progress report.
ok = VP8EncAnalyze(enc);
// Analysis is done, proceed to actual coding.
ok = ok && VP8EncStartAlpha(enc); // possibly done in parallel
if (!enc->use_tokens_) {
ok = ok && VP8EncLoop(enc);
} else {
ok = ok && VP8EncTokenLoop(enc);
}
ok = ok && VP8EncFinishAlpha(enc);
ok = ok && VP8EncWrite(enc);
StoreStats(enc);
if (!ok) {
VP8EncFreeBitWriters(enc);
}
ok &= DeleteVP8Encoder(enc); // must always be called, even if !ok
} else {
// Make sure we have ARGB samples.
if (pic->argb == NULL && !WebPPictureYUVAToARGB(pic)) {
return 0;
}
if (!config->exact) {
WebPCleanupTransparentAreaLossless(pic);
}
ok = VP8LEncodeImage(config, pic); // Sets pic->error in case of problem.
}
return ok;
}